- Iran has moved thousands of centrifuges to a fortified underground site near Natanz called Pickaxe Mountain
- The Pickaxe complex is buried over 300 feet beneath granite, making it harder to target than previous sites
- US President Donald Trump warned that the Pickaxe complex could soon be a target for a heavy US strike
Iran has reportedly moved thousands of nuclear centrifuges into a heavily fortified underground complex near Natanz known as Pickaxe Mountain, making them far more difficult to destroy in airstrikes.
According to a Wall Street Journal report citing US and Israeli officials, Israeli intelligence believes the transfer took place last autumn, months after the 12-day conflict in June 2025, when US and Israeli forces struck several of Iran's nuclear facilities.
The Pickaxe site escaped those attacks and has also remained untouched since a more aggressive aerial campaign began on February 28.
Buried Under 300 Feet Of Granite
The facility is believed to be buried more than 300 feet beneath solid granite, making it significantly deeper than the enrichment plants at Natanz and Fordo that were bombed in 2025.
The Wall Street Journal reported that satellite imagery and intelligence have shown truck movements and construction activity around the mountain for roughly 15 months, suggesting the site has been steadily developed.
It remains unclear where the centrifuges came from, although officials believe they may have been relocated from other Iranian nuclear facilities.
IAEA Kept In The Dark
Iran has not allowed inspectors from the International Atomic Energy Agency (IAEA) to visit the Pickaxe complex and has provided no detailed information about what is happening inside.
IAEA Director General Rafael Grossi said in March that Iran had informed the agency back in 2021 that it intended "to have nuclear activity" at the Pickaxe site.
The lack of international access has fuelled concerns that the underground facility could be used for activities hidden from global monitoring.
'Pickaxe' Could Be Next: Trump
US President Donald Trump has repeatedly signalled that the underground complex could soon become an American target.
Last week, he said, "Pickaxe is a possible target for a nice big fat shot right near the front door," adding that the US would "probably give Pickaxe a shot relatively soon".
Speaking to reporters on Tuesday, Trump escalated the warning, saying the US would strike the area where Iran's centrifuges are believed to be located "pretty soon" and "very heavily", while insisting Tehran would be powerless to stop it.
'Worst-Case Scenario,' Says Former US Official
Nate Swanson, who served as the US National Security Council's director for Iran during the Biden administration, warned that the reported activity at an undeclared nuclear site was deeply concerning.
"A covert breakout is the worst-case scenario," he said, referring to the possibility of secretly producing a nuclear weapon.
"We don't know what Iran's intentions are, but the fact that we can't verify this site underscores how problematic the status quo is."
Iran Denies Military Nuclear Ambitions
Iran has consistently maintained that its nuclear programme is meant only for civilian purposes.
However, it has enriched uranium to levels just below weapons-grade purity, a threshold experts say has no practical civilian use and has long raised alarm among Western governments and nuclear watchdogs.
